Should you believe what a chicken 'expert' is telling you?

Who: Dr Maurice Pitesky, DVM

Where: University of California, Agriculture and Natural Resources

Web: ucanr.edu/sites/poultry/

Source: blogtalkradio.com

Karen from Auckland says she's never wormed her hens, but she feeds them raw garlic and it keeps them worm-free. Brad from the Wairarapa tells everyone he's never worn a dust mask or respirator while cleaning a coop in the 30 years he's owned chickens, and nothing has ever happened to him. They sound convincing. They write emphatic posts on social media or on their long-running poultry blog.

Online information and support are two excellent resources when you're learning to care for poultry, but it can be hard to know whether to trust people like Karen and Brad.

Dr Maurice Pitesky is a US vet and researcher who specialises in poultry disease and health. These are his tips for checking the scientific efficacy – or lack thereof – of information you hear or read online.

Beware of simple answers

Most importantly, Dr Pitesky says watch out for what he calls black and white statements.

“If someone says something like ‘apple cider vinegar works against coccidiosis,' that is a very simple answer. There are nine species of coccidia and even the best medical treatments we have don't treat all nine.

“If they give you a complex answer and references, it's possible we're probably talking about something realistic.”

Be sceptical of an anecdotal source

Scientists use the scientific method to test a hypothesis, which includes:

• making observations;

• taking measurements;

• conducting experiments.

“I was at a poultry presentation where it had a list of simple answers to health issues. It's really important to be sceptical of that, even if you hear someone who's a good speaker, they're authoritative, they're funny, they're confident, they may have even written a book or two. It doesn't mean they know what they're talking about. It's on you to vet it, and you can do it yourself.”

If a person says their findings are based on their personal experience, you need to ask questions.

“If they say apple cider vinegar works against coccidiosis, you'd want to know:

• do they know what type of coccidia they were treating?

• what breed (of poultry) was it?

• what tests did they use to see if they were successfully treated?

• were they only looking at clinical signs? “If their answer is curt and they'll only say, ‘I have 30 years of experience,' that's not a reasonable science-based answer.”

When scientists produce research papers, and then write an article, it's peerreviewed. This means independent experts take time to check every aspect of it.

“If I send something to a scientific journal, they don't just publish it. They send the article to three other experts in the same field who you don't know – or if you do, they won't tell you they're reviewing it – and they vet it, check it. If they agree with what I've written, then the article will be published. Compared to something (anecdotal) written on the internet, it's a completely different level of vetting.”

Look for more than one study

When scientists do a study, funding is always limited, so they only answer one or two specific questions. You want to find multiple recent studies proving something has worked.

“You might find an article saying that E. coli can be treated (with this ingredient). Are there 5-10 papers recently that have looked at the topic? Is it an article from the 80s or 90s? More recent literature might say a different thing.

“Science gets things wrong all the time, but usually, it gets caught eventually. And I want to know under what conditions it works – that's where science comes in.”

It's only recently (in the last 10-15 years) that it has been possible for scientists to publish negative results. In previous decades, if an experiment showed something didn't work, it wasn't published.

“Now there are journals that specifically publish negative results. If something doesn't work, say a medication to treat coccidiosis, you want to see those results because they're just as important as positive ones.”

Don’t be put off by the scientific jargon

Reading scientific papers can be daunting, even for someone like Maurice, who works in research at a prestigious university and has 25 years of experience.

“When I read papers, I can barely understand some of them sometimes,” says Dr Pitesky. “They're often hard to read. There's nothing wrong with reaching out to ask or email the study's author to clarify the results. Scientists love talking about research – if you ask a question about a paper, they will talk your ear off and be so happy that someone paid attention to their study.”

How scientists look at ‘new’ fads

A simple cure often gets ‘stuck' on the internet, says Dr Pitesky.

“People start repeating it, and there's an echo chamber effect.”

But when you put it under scrutiny, a fad can quickly fail to meet basic scientific principles.

If a scientist wants to do a study, they must show its ‘mode of action.' For example,

to increase egg production in poultry, research shows broadly, the modes of action are:

• light levels in the environment;

• energy and protein levels in feed;

• calcium, phosphorous, and macro minerals in feed.

“One thing I've heard about recently is the idea of red pepper flakes increasing egg production in winter. You can't just ask for a $100,000 grant to do a study on red pepper flakes' effect on egg production – I'd have to show a mode of action. What is it in red pepper flakes that would cause an increase in egg production?

“If I look on Google Scholar, PubMed, the Web of Knowledge, all these different databases of scientific articles, I can't find any evidence about (an active ingredient in) red pepper flakes. I also can't see any mode of action from what we know about red pepper flakes that would be consistent with increasing light, or energy, protein, calcium or phosphorous.”

In the last decade, scientists have shown that many natural products can positively affect poultry health and productivity. Some of the latest research findings include:

• green tea, nettle, pennyroyal, yarrow, and alfalfa seeds, powder, and extracts can improve poultry immunity, reduce the growth of pathogenic microbes, and improve the viable counts of lactic acid bacteria;

• lavender, alfalfa, and nettle powder improve egg yolk colour;

• ginger reduces fat content in meat;

• flax seeds increase alpha-linolenic acids and omega-3 fatty acid content in chicken tissue, and improve quail egg hatchability;

• plant metabolites, particularly carvacrol (found in oregano and thyme) and thymol (found in thyme) are natural growth promoters and improve immunity.

But for all the positive natural news, some myths persist, says Dr Pitesky.

Raw milk

There's a lot of information online about raw milk acting as a natural probiotic to treat gastrointestinal issues in poultry. It's completely wrong, says Dr Pitesky.

“Raw milk, and any dairy products, contain lactose, and birds can't digest lactose. Also, it won't work (as a probiotic) because milk and other dairy products don't have the millions or billions of beneficial bacteria that you find in probiotics.”

He says it's also a perfect example of how a ‘natural remedy' can actually cause harm.

“If birds have one problem, they're tough, they won't show any signs of disease, for example, if they have an E coli infection. But give them a second problem, like feeding a diet they shouldn't have, and then the first problem can become a big problem. Usually, if a bird has 2-3 problems, that's when you start seeing clinical signs of disease.”

There are manufactured probiotic products for poultry. They're especially useful for chicks and young birds, as they help seed the gut with ‘good' bacteria, improving their digestive system over their lifetime compared to birds that don't receive them. A probiotic might be one option of many to consider when

"You can't just ask for a $100,000 grant to do a study on red pepper flakes."

4 natural poultry ‘remedies’ that aren’t proven by science

a bird is sick, but there’s no evidence that they treat gastrointestinal infections.

Pumpkin seeds

Another popular myth is that pumpkin seeds act as a dewormer. There’s no literature on it in chickens, says Dr Pitesky, although there have been studies in other animals.

“I was surprised to find there have been studies in other animals, including cats, where they used pumpkin seeds and other seeds from squash in order to reduce parasites like tapeworms.”

However, you can’t make a leap and assume the same thing will work in poultry.

“One, you’re switching species, and you’re also assuming all parasites are created equal, which they’re not. There are all these variables, in the animals, the treatment, what seeds were grown, what species of squash were they, how do you prepare them? If there’s an active ingredient in there and you inactivate that ingredient, you might be feeding pumpkin seeds, but it won’t work.”

Different varieties of pumpkin have seeds that contain varying amounts of amino acids, which may have anthelmintic

properties. One of them, cucurbitacin, tested in vitro (in a lab) was effective at killing round and tapeworms. Levels of amino acids in seeds vary depending on the variety of pumpkin and how it's grown. Scientists don't yet know what specific amino acid (or a mix of them) is effective against parasites, or what level would be needed to successfully treat an animal.

Dog & cat food as a diet for moulting birds

During a moult, birds shut down their reproductive tract, lose their feathers, then grow them back. Feathers are about 85% protein. That's led some people to think feeding them a protein-rich diet such as cat or dog food will help.

“But cat food especially is really high in salt, and that's not conducive to a good poultry diet,” says Dr Pitesky. “There are guidelines for different animal feeds that look at the requirements for protein, salt, calcium, phosphorus, and those are not identical.”

Sand as bedding

Some poultry owners use sand as bedding and treat it like cat litter, scooping up manure and removing it. However, sand isn't suitable for poultry.

“Sand is abrasive and can scratch the bottom of their feet and cause bumblefoot, an infection in the feet,” says Dr Pitesky. “(Chickens get bumblefoot) because of husbandry practices that aren't ideal. They get small scratches, then pick up bacteria in the environment – E coli, staphylococcus – which causes a bumblefoot infection, and it's really hard to treat. There are antibiotics, but it's really hard to get them to the foot in the right concentration.”